I 'll first describe how the '14 is set up, then what I'm thinking and why, then you guys take it from there: Front: 21mm front T bars, 19mm weltmeister sway bar, set about 1/4 in from full soft, koni oil (911) sport adjustables in shortened housings, usually run at 1/2 turn in from full soft. Allignment as much neg as I can get, which is about 1 1/2 per side, 1/8 total toe out, caster at high end of factory specs. Back: Koni gas sports, (914), run full soft, 175# springs, threaded adjusters, no rear sway bar, no toe and no neg camber. Koni competition bump stops all the way around. Stock 15 x 5.5 rims w/Azenis, going to kuhmo or hoosier for next season, on either factory rims or 6.0 panasports. Rack spacers up front. Lowered to about 2-2.5" of travel for front struts before hitting the bump stops, back end lowered to corner balance to 49/51 diagonals. Open diff. 2.0 motor, soon to be kitcarlson'd, kerry hunter header w/supertrapp, "custom" (home-made) cold air kit, basically a K & N mounted on some pvc on top of the throttle body that sits right under the engine lid mesh w/the rain tray out.
I like the way it handles, in specific, the throttle lift oversteer at higher speeds to rotate around a cone. The car will be DSP for next season. Don't like the body roll. I think from seeing photos there is too much.
Plan of attack? I have always thought getting spring rates right was the first step, then sort the F/R balance with the sway bars, and fine tune at the track with shocks and air pressures, in that order. Here's what I'm thinking- go to the 23mm front sway bar, adjustable drop links to make sure there is no pre-load, add the (?) 18mm rear adjustable bar. Increase both bars a similar amount to try to retain the front/rear balance, and hopefully lose some body roll in the deal. Maybe go back to the 150# springs sitting in the garage.
Use is auto x, no lapping or road course stuff. (yet)
So, how about it? Anyone been there/done that? Most of the folks I've talked to locally stay away from a rear bar. I like the F/R balance the car currently has, and know how to fine tune it w/shocks/tire pressures for the conditions of the day. When I have tried to tighten up on the front bar, it just seems to become a pushing machine, and with the shocks set other than noted, it rides like a dump truck. Just gotta get rid of some roll, or just get used to it. waddya all think?
Unless you have an LSD or gobs of power I would not use a rear bar for AX or on a tight course.
In the past, I tightened the front bar until it "pushed" and then backed off a full turn.
do you have a roll-cage or bar?
if not, you'll always have body-roll, regardeless of your setup as the body itself twists around the center ...
i have a 22mm front bar and 180lbs springs in the back and virtually no roll whatsoever, thanks to the full cage.
Andy
As Joseph says, go to a 23mm sway bar and also heavier rear springs like #200 non progressive ones. Then play with the settings on the shocks to set the car up. If the front is really tight (heavy T bars and sway) and the rear is pretty soft you can lift the front tire right off the ground (not good) because the rear will squat (roll). Balance is real important.
Go to 5 lugs and get some 7x15 cookies (cheap) to go with the Kuhmos (205's) and get some traction.
Geoff
Looking at your settings again, I think it might be worth your while to look over these "basic" suspension guidlines for our cars. I think Dave Darling collected this info as a basis to start from. I hope this file doesn't weird out when I copy it.
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Alignment suggestions:
1. Front caster either stock (6 deg) or max you can get and have both wheels even. Street tires, stock suspension, reasonable driving:
-0.5 deg camber front
-1.0 deg camber rear
~1/16 inch toe-in front and rear.
2. Street tires, stock suspension, fairly aggressive driving or some autoX:
-1.0 deg camber front
-1.5 deg camber rear
~1/16 inch toe-in front and rear; possibly ~1/32" toe-OUT in front for a car biased more for autoX.
3. I wouldn't go much past this setup for any car with street tires.
Sticky tires, 140# springs/stock torsions/19mm front sway bar, autoX with some street:
-1.5 deg camber F
-2.0 deg camber R
~1/16 inch toe-OUT front
~1/16 inch toe-IN rear
4. Sticky tires, 220# springs/21mm torsions/22mm front sway bar, track w/some autoX:
-2.0 deg camber F
-3.0 deg camber R
~1/16 inch toe-OUT front
~1/16 inch toe-IN rear
Note that these are all very much "general recommendations". Everything from exact choice of suspension components, to exact tires, to pavement, to driving style all affects the setup!! So these might be a half-decent place to start from, but to find the "right" place you really must test and tune.
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I think you would fall into the #4 category.
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I would suggest the following:
I would increase the stiffness to your present front bar (to eliminate lean), add some negative camber to the rear (better contact patch for traction), and go to stiffer springs (200-230#), in the rear to keep the car from pushing (and will also help eliminate lean).
You should be able to eliminate the unwanted lean you mentioned, but still maintain your car's balance that leans towards oversteer - for only the cost of rear springs.
well, plus the cost of your forum dues.
yup! then go have some fun!
Geoff
Thanks for the replies- some more info on the car and thoughts- Jospeh222- what did you find odd about the set up? As for going back to the 150's w/a rear bar, I didn't want to over-stiffen the back of the car, but from what has showed up in the thread, sounds like it might be hard to get too stiff w/the springs- this is a little worry for me, as I'd like a somewhat compliant ride to and from the events, which are usually 2+ hrs each way away from me. Why is it that everyone just goes bigger and bigger on the spring rates, and few go w/rear bars? What about that magic word, "balance"?
I think I've got the front bar nearly as stiff as I dare w/out more push. I do have a factory rear bar kicking around the parts bin I call a garage- how about that w/the 150's or 175's on the back, and just tighten up on the 19mm front, rather than spend $$$ on the 23? Reasonable or not?
As for chassis stiffness, I've added the Brad Mayeur rocker kits to both sides, and while there is no roll cage, its pretty impressive to jack it up and see no door gap changes, and this was a solid car to start with, no rust-o-ration project. A friend has the autopower full cage in his car, would it make THAT much of a difference?
I have a library of 914 articles, as many of us do, and refer back to a copy of "autocross" magazine, from about 1991, (currently grassroots motorsports) that porfiles David and Ellen Ferguson's 914-6, FP class, 2nd at the Nats that yr. Their set up at the time was 21mm T bars, 22mm sway up front, and in back an 18mm sway with 165 springs. Do you think this worked for them as they had- 1) more power, and 2) true slicks, not DOT tires.
Here in the middle of nowhere WI the driving season is pretty much over, but that means the wrenching season is just starting up... keep the ideas flowing. What setups are each of you using ?
Hey, Dave-o, are you AKA David H., and did you leave the valley fair event early? If so, come to the club meeting tomorrow night- I am meeting Rob M. there, (red 914) to talk parts swaps, set ups, at 6pm, official club meeting starts 7:30pm.
p.s. At Davanni’s Pizza on Riverside right?
You don't need a cage to stiffen the chassis, especially a bolt-in one.
The concern about a rear anti-sway bar is due to the common problem of the inside wheel spinning when powering out of corners. Since you have the rear bar, I say put it on and stiffen the front bar to match. If you don't like it you can disconnect the rear bar anytime.
Actually a Weltmeister adjustable rear bar can be set up softer than the factory rear bar which may limit some body roll without causing as much loss of traction on the inside tire.
With stickier tires you should be able to tolerate more rear stiffness with less tendency to spin the inside tire.
ok...me again.
31mm front bar 2/3 towards soft.
stock torsion bars
150# rear springs
stock rear bar
Koni yellow adj's all around ( front firm, soft rear)
Engman's weld-in chassis stiff kit in the inner longs.
Perfect
Very streetable and perfect rotation.
KT
Would progressive springs solve his drive to, and then autoX concern?
I've learned some stuff about suspension for AX in the last few years..... mostly by finding out "oops, that didn't work" and as you go faster stuff that you thought worked just fine no longer cuts it.
Mostly I've been playing catch up with grippier tires.....hay, you start going faster (seat time helps too) revealing handling quirks that you didn't know you had
One of the few "fer sures": If you're set at full soft on your front AR bar & you're still pushing, you've got a problem. (Unless you have one end or the other breaking loose consistently, you ain't going fast enuff.)
The "no rear AR bar to keep the back inside wheel on the ground" ditty works till it don't no more. Mines on the ground but leaves a long black streak around some corners.If your have more tire than power, this won't be a problem tho.....or you ain't going fast enuff.
An aside: I drove Jim Chamber's car at the last AX. Seemed well balanced on the first run as I was feeling it out.
Pushing it some an the next run revealed a oops. He has a rear AR bar. In a sweeper, power on....nice drift....picked up the inside rear tiar...speed fell off, got lotso grip, dipsy doodle readjustment of line....lost momentum....prolly lost a second right there. Now he has a challenge.
So..... I what to do with my problem?
Get an L$D?....ouch! Being a CSBO sux.
.
Stiffer rear springs.....this I will try a set of 275s & 300s one of em' ought to be about right....I can always stiffen the front AR bar iff'n it goes loose.
More tiar....sure, why not. I can go to monster meats in my class....getting fender over em' is gonna keep that down a bit tho.
BTW, Bob, progressive springs will really screw up an AX car's handling....if you're going fast enuff.
BTW II, what's happening with the ALL 914 AX?
March sux for me. I won't time to set a handle on my new set-up. I'd hate to come down there & stink up the joint.
I've got a set of 165 progressives on my street car. I like the way it feels, but I don't have much to compare it with. It was either that, or a set of 140s. Do you think I made the wrong choice? Exactly how would it screw up the handling?
The way I understood it, softer ride on flats, stiffer in the corners. If you're used to the way it handles, isn't that what makes a difference?
Thanks, I understand now. In any racing situation you want to minimise roll, hence the heavier springs. And, coming out of a high speed turn you want it to be constant, rather than have it go soft on you as you come out of the turn and possibly cause oversteer. I had a choice to make for my street teener between 140s and 165 progressives. I wanted to have a comfortable ride on surface streets (tracks don't have potholes), and less body roll when cornering. Do you think I made the right choice? I've done right hand turns at 50, and four wheel drifts, with complete control. And, that's with stock tie rods! I haven't gotten around to putting turbo tie rods on it. Do you think I'll notice a dramatic difference?
Thanks, that clears up the oversteer question. It's going in, not out, where the oversteer occurs. Still doesn't answer all my questions though.
Still looking for opinions on my choice of the 165 progressives instead of going with the 140s.
Depneds on your use. In an earlier evolution of my car, I had the 165 progressives on it, and for street driving, and some spirited back roads, they were a good compromise, I liked them. When I got seriously bitten by the auto cross bug, I switched to adjustable coil overs and straight rate springs for the back, and liked them better for that purpose. This suspension set up thing is all about compromise- lower ride height = better handling but less clearance to road hazards. stiffer springs = better handling on the track, but a choppier ride on the road, and so on.
Figure out whats important to you, and set it up accordingly. Compromise. Thats what I'm trying to figure out currently, rear spring rates vs rates + sway bar vs front rates + bar... throw in allignment settings and sticky or not so sticky tires, and you've got a real can of worms to sort out! But for some of us sick mechanics, thats half the fun...
Back to the original question of this thread. I have another opinion.
I think you're too low. Unless you've done something to change it, your roll center is way below ground, which forces one to use too much front bar to counter the roll.
You mentioned that your struts are shortened, what angle are your control arms? Anything other than lower at the ball joint and higher at the body will cause the roll center geometry to work against you. Hell, it does even in that condition, but not as bad.
I autocrossed my 914 for years and the thing leaned like crazy, since it was too low for the factory geometry.
BTW... it will only get worse with stickier tires.
replies to replies-
Bleyseng or others: will 7" cookies fit the stock fenders, and yes, I realize no 2 914's are the same... what is the offset and back spacing of that wheel?
RacerChris: would adding the R bar but softening the springs, (175-150) allow for more roll stiffness w/out greater risk of inside wheel spin on corner exit?
Trekkor: 31mm front bar?!?!?! should that have been 21mm?
Groot: great question. I went to the garage to check it out. The actual travel I have before the shortened front strut hits the bump stop is closer to 3.5" or so. Ride height to the front donut is 5 1/8", to the rear just over 5 1/2". The ball joint is without a doubt the lowest part of the front "A" arm, if you can call it that, by maybe an inch or so. I have seen other 914's from race prep "shops" that are pretty slammed- are there other suspension set up tips to work with that ride height, or do these "shops" not have a clue? I have been doing alot of reading on the topic of suspension, and understand what you are getting at about the roll center being to low. Sounds like you ran your '14 way low- how did you deal w/it riding on the bump stops, and did you just throw a ton of bar at it to control the roll as best as you could?
As others have spoken of wheels, would a set of diamond racing challenger 14" wheels be a good idea for a cheep, wide, although slightly heavy means of lowering the center of mass of the car? And if so, what are the specs of the cookie cutter wheels so I could have that matched to try to get the right offset for a wider wheel on a '14?
Great. Sounds like the front roll center is not your problem.
My car wasn't way too low, just too low for the suspension to work properly. I was building another race car at the time and was only keeping the P-car running for autocrosses. BTW... the other car I built has the same "lower it too much and it doesn't work worth crap" issue.
The cookies will fit if you massage the fenders some. (roll the fenders) The only 7" rim that is drop in would be the rare RSR fuchs that go for $1600 a set. If you have a 4 bolt you can run the 914 6" Fuchs and they fit ok with a 205x50x15 Kuhmo. They bulge alittle bit so the 7" cookies seem to get more tire on the ground to me when I ran chalk tests.
The offset of the 914 2.0L Fuchs is 4 7/8" and the cookies are 4 5/8"s.
Hmm, I am running about 4 3/4" inches to the dougnuts and still want to go lower.
If you want to have a comfortable street ride then bigger tires are the way to go say 195x 60 to give you more "mush". Even on street tires my car is ok around town and rock steady on the freeway. I drive about an hour on the AX tires to race and it does get tiring. The solution is to take someone along to help drive!
Geoff
Groot- did you find a happy medium (not a halloween joke) between to low, to stiff, to slow, in terms of ride height, spring/t-bar rates, and roll bars?
Bleyseng- were your fingers going faster that your brain? I always thought all the factory 4 bolt alloys were max of 5.5, you mention a 6 inch fuchs? I've got a line on a set of 1 yr old panasports with some hoosiers that are 1 event old, that may end up on my car next season, if the price is right. If not, I have a spair set of 4 bolt fuchs that will get Kuhmos. I suspect they will ride with me in the car for the long trips to and from the events, and I'll just leave the dry, crusty, 2 season old azenis on for daily driver skins. What is your set up, and how do you like it, considering you're lower than me...
No, sir, but I wasn't futzing with that car, at the time. I was just autocrossing it when I wasn't racing. I spent my time working on the race car.
Now, the ITB VW is gone and the 914 is the race car and I've completely modified the front suspension and now run on slicks, so comparisons are not possible. If interested, pictures are in this thread:
http://www.914world.com/bbs2/index.php?act=ST&f=2&t=16575&hl=ep
You heard me, 31mm! front bar.
Totally adjustable. Excellant bar.
Turbo tie rods- I was laughhing all the way home, they rage.
I'm leaving to get my new tires right after this post.
KT
Attached image(s)
your 19mm bar = solid
trekkors 31mm bar = hollow (available in 27mm I think as well) SmartRacing
my 25mm bar = hollow (Tarett Engineering)
how does tarett rate their bars?
oops, yup I meant 5.5" Fuchs. If you are still four bolt then you could always have a set of steelies welded up to be 6 or 7 with the right offset to stay cheap. Brad said he had a line of someone who will do this. I'd go with the fuchs until you can switch to 5 bolt setup where there is more choices. Its all about choice right?
I am running 21mm Tbars and 21 sway bar and 180lb rear springs. Have some 200# to put on but no time. Koni's up front and Bilstiens in the back. 7x15 cookies with Kuhmos. Car is pretty neutral and I am not driving to the level of the set up.
My son Blair drives the car faster and usually is up in the top 3 of our race group.
I wish I had my car at the WCC for that course as it was wayy fun even in RichL car. I still get back to keep the car balanced and then slowly change things as you improve or your driving skills exceed the cars capablity. With a stockish car thats easy but after throwing lots of money at the car drive it instead of adding more stuff. Find out what it can and can't do like when it was stock.
Like I said I really like the 7's as they work well. Just can't decide if I want to flare the car yet.
Geoff
I run stock torsion bars.
Get a bigger bar.
Find someone who has really good set up who will let you ride/drive.
KT
If I can help it... I dont like to "spring" the cars heavy in the front. I would rather have the HUGE range of adjustment on a big front bar than to have BIG torsion bars that I cant do anything with as far as changing their rates quickly. I also adjust 5-6 914's at EVERY autoX for that given surface/track/event. We dont drive each event on the same setup so I want as much adjustability as possible (big bar small torsion bars/Koni's)
Also..
The alignment is driver dependent. A PRO IMSA/ALMS driver requires a totally different alignment than say JP or me would need. The PRO driver will be pushing the tires MUCH harder which would require a more aggressive alignment. My point: dont listen to a single person on "what you should have". There is NO way for me to tell anyone what they need without tire temps/pressures. THEN I go back with the numbers and decide what kin of driver YOU are and determine what you need for the tires you decide to run. I'm REALLY tired of all the race shops throwing their "race aligments" on cars without EVER asking the owner about his driving style.. I even ask 914 people for their lap times at local tracks to determine whether or not they know their ass from a whole in the ground. Put a race alignment on a Newbies cars and he will wear the tires out FAST and be pissed that he spent good money on tires only to wear them out because he wasnt using them... no thanks. I'll make some calculated "guesses" for my clients.
B
Brad is right, of course. It's hard to know exactly what you need....if anything.
If you don't like body roll with your present tiars, you're gonna hate it with the Kuhmos. More grip=more lean.....
My best guess..... 250 lb rear springs. You've got lots of adjustment in the front AR bar to dial out (stiffen the bar) excessive oversteer should the need arise.
Question for Brad- If you're supporting the idea of stock T bars in front, with massive roll bars, why is the majority opinion for the back of the car to do the opposite- no bar and heavy springs? Not trying to be an idiot here, just understand. Sure, the front steers and the back drives, but beyond that, if we're trying to reach the same compromise, that is good handling, why are the theories so different one end of the car to the other?
I can buy rear spring rates in 25lb increments and change them in less than 15 minutes with some help. I do install rear roll bars in EVERY 914 regardless if has a LSD or not... again... I want the adjustability of that rear bar (connected or not connected) The rear bar is worth something like 60lbs of rear spring rate. They are very easy to disconnect. I have asked two vendors for NEW adjustable rear bars for our cars... we will see who jumps first. I sell both of their front bars.
Everyone can drive a 914 that oversteers (boil the rear hides with more throttle).. no one can drive a understeering car (I meant very few).. so increasing rear spring rates (or adding/removing rear bar) is much easier than trying to do this with torsion bars in the front.
B
This thread seems to have run its course, time for a wrap up and any final comments from the crew-
Plans for next season: leave the front end alone with the 21mm "T" bars and the 19mm sway. Add camber plates and to get a little more than the 1.5 neg I can get now. Match the rear camber to what I can get in the front. Play around a little w/ the toe out front-toe in rear. Leave the 175# springs in the back. Add the factory rear bar, since its in the garage, and my labor is cheep. Sticky tires for auto x. If I can talk the panasports and hoosiers off my friends car, run those, if not, buy some kuhmos for the 4 bolt fuchs stacked in the corner. Unless other interesting wheel options present themselves over the winter. Lower the car maybe 1/2 inch more all around, keeping the ball joint location in mind, and re-corner balance. Adjust front sway and shocks to taste.
Go fast, have fun. The snow isn't even here, and I already am ready for it to be gone...
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